diff --git a/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/lib/Transforms/Scalar/LoopStrengthReduce.cpp
index bd1f21c69eb..28d94497a3e 100644
--- a/lib/Transforms/Scalar/LoopStrengthReduce.cpp
+++ b/lib/Transforms/Scalar/LoopStrengthReduce.cpp
@@ -3805,6 +3805,7 @@ void LSRInstance::GenerateTruncates(LSRUse &LU, unsigned LUIdx, Formula Base) {
       if (!F.hasRegsUsedByUsesOtherThan(LUIdx, RegUses))
         continue;
 
+      F.canonicalize(*L);
       (void)InsertFormula(LU, LUIdx, F);
     }
   }
diff --git a/test/Transforms/LoopStrengthReduce/X86/canonical-2.ll b/test/Transforms/LoopStrengthReduce/X86/canonical-2.ll
new file mode 100644
index 00000000000..69bae3a5115
--- /dev/null
+++ b/test/Transforms/LoopStrengthReduce/X86/canonical-2.ll
@@ -0,0 +1,36 @@
+; REQUIRES: asserts
+; RUN: opt -mtriple=x86_64-unknown-linux-gnu -loop-reduce -S < %s
+; PR33077. Check the LSR Use formula to be inserted is already canonicalized and
+; will not trigger assertion.
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+
+; Function Attrs: uwtable
+define void @foo() { 
+cHeapLvb.exit:
+  br label %not_zero48.us
+
+not_zero48.us:                                    ; preds = %not_zero48.us, %cHeapLvb.exit
+  %indvars.iv.us = phi i64 [ %indvars.iv.next.us.7, %not_zero48.us ], [ undef, %cHeapLvb.exit ]
+  %0 = phi i32 [ %13, %not_zero48.us ], [ undef, %cHeapLvb.exit ]
+  %indvars.iv.next.us = add nuw nsw i64 %indvars.iv.us, 1
+  %1 = add i32 %0, 2
+  %2 = getelementptr inbounds i32, i32 addrspace(1)* undef, i64 %indvars.iv.next.us
+  %3 = load i32, i32 addrspace(1)* %2, align 4
+  %4 = add i32 %0, 3
+  %5 = load i32, i32 addrspace(1)* undef, align 4
+  %6 = sub i32 undef, %5
+  %factor.us.2 = shl i32 %6, 1
+  %7 = add i32 %factor.us.2, %1
+  %8 = load i32, i32 addrspace(1)* undef, align 4
+  %9 = sub i32 %7, %8
+  %factor.us.3 = shl i32 %9, 1
+  %10 = add i32 %factor.us.3, %4
+  %11 = load i32, i32 addrspace(1)* undef, align 4
+  %12 = sub i32 %10, %11
+  %factor.us.4 = shl i32 %12, 1
+  %13 = add i32 %0, 8
+  %indvars.iv.next.us.7 = add nsw i64 %indvars.iv.us, 8
+  br label %not_zero48.us
+}
+